The human body is a structure that constitutes a subtle and complicated electric field environment, consisting of approximately 60 trillion cells, on which the organs in the body depend for metabolism and regeneration on a daily basis in order to maintain the phenomena and functions of life. The metabolism of cells involves a great variety of mineral ions. For example, potassium ions in the intracellular fluid exchange with sodium ions in the extracellular fluid within one hundredth of a second, generating an electric potential generally known as the “action potential”. When the electric potential of the human body is in equilibrium, physical health ensues, and from the perspective of traditional Chinese medicine, such equilibrium is a harmony between qi and blood, or yin and yang. Conversely, failure to keep the electric potential of the human body in equilibrium leads to diseases. In fact, medical science has proved that the impedance of certain points on a person's skin drops when the person falls ill, and this clinical observation is in line with the theory of “acupuncture points” in traditional Chinese medicine. From the physiological point of view of traditional Chinese medicine, there are about 730 acupuncture points distributed over the entire human body. The acupuncture points are the foundation of acupuncture, which is a treatment based on the “salt bridge theory”, according to which electrical connection (i.e., ion exchange) between at least two metal needles inserted in the skin can activate related cells, stimulate the meridian system, and bring about normal physiological functions of the body. Nowadays, all the electrotherapy devices on the market are applications of Chinese acupuncture, the first ones being invented by Dr. Yoshio Nakatani, a doctor of medicine of Japan. With continued research and development efforts and incessant improvement, such devices have been able to promote blood circulation as well as metabolism and are in extensive use in hospitals and homes due to their effectiveness, safety, and zero side effects. In Japan, the US, and many European countries, electrotherapy devices have even become essential household devices for health maintenance. Typically, referring to FIG. 1, a conventional electrotherapy device 10 includes an electrotherapeutic signal generator 15 (e.g., a transcutaneous electrical nerve stimulator (TENS) or electronic muscle stimulator (EMS)) and a plurality of electrode pads 12. The electrotherapeutic signal generator 15 is configured to generate a series of electrical nerve stimulation pulses. Each electrode pad 12 includes an electrode 121 coated at one end with a thin film of self-adhering water-based silicone gel 122 so that the end of the electrode 121 can be adhesively attached to an acupuncture point on a patient's head, neck, or shoulders via the silicon gel 122. The opposite end of each electrode 121 is electrically connected to the electrotherapeutic signal generator 15 through a conductive wire 13 in order to receive the electrical nerve stimulation pulses generated by and sent from the electrotherapeutic signal generator 15 and deliver the pulses to the corresponding acupuncture point on the patient's head, neck, or shoulders through the aforesaid end of the electrode 121 and the silicon gel 122 coated thereon. The conventional electrotherapy device 10 can therefore perform an effective electrotherapeutic massage on the intended acupuncture points on the patient's head, neck, and shoulders to relieve pain from those body parts. Depending on the range of current frequency of the electrical nerve stimulation pulses generated by the electrotherapeutic signal generator 15, the conventional electrotherapy device 10 can be categorized as low-frequency or medium-frequency. With continued reference to FIG. 1, a low-frequency electrotherapy device 10 refers to an electrotherapy device whose electrotherapeutic signal generator 15 generates electrical nerve stimulation pulses of a current frequency ranging from 2 Hz to 150 Hz. Such low-frequency electrical nerve stimulation pulses can directly stimulate and excite muscle and nerve groups about 1 cm below the dermal tissues as a way to treat diseases associated with epidermal nerves or muscles. In addition to providing a general pain-relieving or anesthetic effect on superficial muscles, this type of electrical nerve stimulation pulses can promote blood circulation in the skin and improve nutrient transport in related tissues. However, as low-frequency electrical nerve stimulation pulses tend to stimulate cortical neurons to a relatively great extent and thus cause pain in the skin, it is generally infeasible to apply a high dosage of current to the patient, and the result is hence limited. Moreover, the high impedance of the human skin to low-frequency electrical nerve stimulation pulses makes it difficult for those pulses to pass through the skin and work on deeper tissues. In particular, low-frequency electrical nerve stimulation pulses tend to cause electrolysis beneath the electrodes and thus burn the skin tissues. In a nutshell, the foregoing drawbacks of low-frequency electrical nerve stimulation pulses prevent long-term high-dosage treatment.
On the other hand, referring back to FIG. 1, a medium-frequency electrotherapy device 10 is an electrotherapy device whose electrotherapeutic signal generator 15 generates electrical nerve stimulation pulses of a current frequency ranging from 1 kHz to 5 kHz. Such medium-frequency electrical nerve stimulation pulses have been used in physical therapy to provide electrical stimulation, or more particularly to carry out an intended treatment through the interference waves generated by two different medium-frequency electric stimulants (the working principle of which is similar to that of beat generation by two signals of different frequencies). This kind of treatment, therefore, is also known as interference-wave therapy or interference-current therapy (or IFC therapy for short). The interference current generated by medium-frequency electrical nerve stimulation pulses can be used to simulate nerves, trigger alternate involuntary contraction and relaxation of muscles, and thereby perform the following treatments:
1. To kill pain by interfering with the pain signal transmission of nerves and by stimulating the secretion of endorphins.
2. To promote blood circulation and reduce edema of the limbs.
3. As medium-frequency electrical nerve stimulation pulses can be used at a high dosage, can penetrate deep to the origin of pain, have low interference, and can help heal body tissues, they are highly suitable for clinical treatment of the following sports injury symptoms: muscle strain, contusion, degenerative arthritis, pain in the lower back, and so on. Furthermore, medium-frequency electrical nerve stimulation pulses, whose current waveform can reach tissues about 6˜9 cm deep from the skin, have good therapeutic effect on acute and chronic inflammation, swelling, and pain.
4. To promote blood circulation and lymph return, improve tissue nutrition, and accelerate self-healing of wounds and bones.
5. Now that the human skin has low impedance to medium-frequency electrical nerve stimulation pulses, it is easy for the current of such pulses to enter body tissues, and there will be no stinging sensation in the skin. Besides, medium-frequency electrical nerve stimulation pulses do not have an electrolytic effect on the human body and hence will not injure the skin and its tissues. These merits allow patients to receive high-dosage treatment with medium-frequency electrical nerve stimulation pulses for a long time.
In consideration of the above, medium-frequency electrotherapy devices have been widely used to perform electrotherapeutic massage on people's heads, necks, shoulders, and backs, with a view to relaxing the related muscle groups and relieving pain from those body parts. Nevertheless, referring again to FIG. 1, patients and physical therapists who perform electrotherapeutic massage on the head, neck, shoulders, and back using the conventional medium-frequency electrotherapy device 10 are almost certain to encounter the following inconveniences and problems that hinder the medium-frequency electrotherapy device 10 from delivering the medium-frequency electrical nerve stimulation pulses steadily and precisely to, i.e., from performing an effective electrotherapeutic massage on, the intended acupuncture points on the head, neck, and shoulders. In the end, unsatisfactory results reduce the users' willingness to use the medium-frequency electrotherapy device 10 again, giving rise to a wasteful use of resources.
(1) While the electrodes 121 of the electrode pads 12 of the conventional medium-frequency electrotherapy device 10 are designed for adhesive attachment to the intended acupuncture points on a patient's head, neck, and shoulders through the thin films of self-adhering water-based silicon gel 122 coated respectively on the electrodes 121, the adhesive attachment surface of each thin film of self-adhering water-based silicon gel 122 does not match the skin surface of each acupuncture point on a patient's head, neck, and shoulders. More specifically, the former surface is a flat plane, but the latter surface, a curved one. It follows that adhesive attachment between the electrode pads 12 and the skin surfaces of the intended acupuncture points on a patient's head, neck, and shoulders may be insecure; that is to say, it is likely that the electrodes 121 are not precisely in contact with the skin surfaces of the intended acupuncture points on the patient's head, neck, and shoulders. Should this happen, the expected therapeutic effect will not be achieved.
(2) During an electrotherapeutic massage session, the electrical nerve stimulation pulses generated by the electrotherapeutic signal generator 15 of the conventional medium-frequency electrotherapy device 10 produce an interference current that stimulates the nerves, causing muscles under the intended acupuncture points on the patient's head, neck, and shoulders to contract and relax alternately in an involuntary manner. Such alternate involuntary muscle contraction and relaxation may lead to detachment, and consequently inactivity, of the electrode pads 12, which may be only loosely attached to the intended acupuncture points on the patient's head, neck, and shoulders in the first place, resulting in accidental termination of the electrotherapeutic massage session.
(3) The thin films of self-adhering water-based silicon gel 122 are a self-adhering water-based material that is sticky only when moist. When the silicon gel 122 has been adhesively attached to the intended acupuncture points on a patient's head, neck, and shoulders for a considerable amount of time or has been used repeatedly in several massage sessions, it tends to dry out due to loss of moisture and thus lose its self-adhesiveness. This phenomenon is particularly evident and serious on patients with dry or hairy skin.
(4) Generally speaking, most patients are unfamiliar with the medical principles of acupuncture points and know little about the importance of positional accuracy of acupuncture points in relieving pain from the head, neck, or shoulders. Consequently, a patient performing electrotherapeutic massage on themselves is very likely to massage the wrong spots such that not only is the intended therapeutic effect not achieved, but also the patient's head, neck, or shoulders may be injured.
(5) Traditionally, a patient receiving electrotherapeutic massage on the head, neck, and shoulders assumes a sitting position, in which the neck supports the weight of the head (about 10˜12 pounds for adults) completely. In other words, the patient's neck will naturally exert a certain force to keep the head upright during the electrotherapeutic massage session. With the patient's neck muscles in tension, however, the expected therapeutic effect cannot be attained.
(6) To prevent the electrode pads 12 from peeling off the corresponding acupuncture points on the neck during an electrotherapeutic massage session, the patient being massaged tends to make a special effort to keep the neck still, but this special effort will strain the neck muscles even more, making it impossible to relax those muscles.
(7) Since most patients receiving electrotherapeutic massage would strive to keep their heads and necks erect and still during the entire massage session, it is all too natural that the patients occasionally turn their heads sideways to relax the tight muscles in their necks and shoulders. Such turns may nevertheless cause the electrode pads 12 to detach from the corresponding acupuncture points on a patient's head, neck, and shoulders, thereby rendering the electrode pads 12 inactive and stopping the massage session prematurely.
(8) If, during an electrotherapeutic massage session, the patient attempts to secure the electrode pads 12 at the intended acupuncture points on the head, neck, and shoulders with their hands, the muscles below the acupuncture points will tighten up because of the lifted arms, thus hampering the expected therapeutic effect.
(9) To address the issue that the silicon gel 122 coated on the electrode pads 12 may end up useless due to loss of self-adhesiveness, disposable electrode pads 12 for a single use were developed. As such disposable electrode pads 12 can be used only once and must be discarded after use, an unnecessary waste of resources takes place, and the large expenses incurred place a heavy financial burden on those who need electrotherapeutic massage.
(10) Owing to the drawbacks and inconveniences stated above, patients and physical therapists who receive or perform electrotherapeutic massage on the head, neck, shoulders, and back via the medium-frequency electrotherapy device 10 often have problem delivering medium-frequency electrical nerve stimulation pulses precisely to the intended acupuncture points on the aforesaid body parts, meaning the acupuncture points are massaged ineffectively. This kind of experience will dampen the users' willingness to continue using the medium-frequency electrotherapy device 10, leading to a waste of resources, which is truly a shame.
In the light of the above, it is important to develop a novel massage device that is configured to perform electrotherapeutic massage on a patient's head, neck, and shoulders; whose compact, simple, and multifunctional structural design allows the massage device to be carried around and operated with ease by patients and physical therapists alike wherever desired; and that helps maintain the natural lordotic curvature of a patient's cervical spine while performing electrotherapeutic massage precisely on the corresponding important acupuncture points on the patient's head, neck, and shoulders, thereby relaxing the nerve and muscle groups beneath the corresponding important acupuncture points; relieving pain from the patient's head, neck, and shoulders precisely and efficiently; reducing muscle tightness in the aforesaid body parts; and by means of the foregoing muscle relaxing mechanism, fine-tuning the corresponding portion of the vertebral column, including the thoracic vertebrae, to its proper position.